Latest tank was about 50% (about 50 miles) highway driving and that bumped fuel mileage up to almost 16mpg.
I originally thought it would only do up to 15 MPG with pure highway driving.
I was able to stay in lean burn (16:1 A/F ratio) pretty much the whole time.
So if you calculate 50% in town, EOC driving that nets 12 to 13mpg and 50% highway driving means I am getting about 20mpg with pure highway driving.
All I did was lean tune the carb and advance the base timing to 12 degrees.
20MPG with a 7.4L, non lockup, non overdrive with 4.10 gears on the highway should not even be possible.
I would be willing to lean tune the cruise a little bit more. Since this is the first micro highway trip, holding a steady load and speed I really wasn't sure what to expect.
I don't consider leaning the carb and advancing the timing as even really trying, this may warrant further investigation.
Wait, didn't some one tell me that an edelbrock 650 carb and an edelbrock Air-gap intake manifold was just about the worse thing I could do for fuel economy?
